<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>04-createElement效率测试</title>
</head>
<body>
    <script>
        function fn(){
            var d1 = +new Date();
            for(var i = 0; i <1000;i++){
                var div = document.createElement('div');
                div.style.width = '100px';
                div.style.height = '2px';
                div.style.border = '1px solid red';
                document.body.appendChild(div);
            }
            var d2 = +new Date();
            console.log(d2 - d1);
        }
        fn();
    </script>
</body>
</html>